世界大學抓舉冠軍選手之槓鈴運動學分析

Kinematic Analysis of Barbell Trajectory in Snatch Champion Lifters at the World University Weightlifting Championship

前言：抓舉之槓鈴動作技術是為快速且連續的動作，動作過程需要減少槓鈴不穩定的前後運動，以此達到省力的效果。本研究利用Chiu et al.(2010)的RBM指數將選手進行分組，以此來探討世界大學舉重錦標賽之抓舉冠軍選手的槓鈴運動表現與瞭解RBM指數的應用價值。方法：利用一台數位攝影機來拍攝選手在抓舉過程中的槓鈴軌跡運動，藉由動作分析系統獲得槓鈴運動學的參數，來比較優組別與中組別之差異。結果：優組別與中組別在七個水平運動學參數：槓鈴經過膝關節瞬間的水平位置(XCK)、槓鈴最遠離垂直參考線之水平位置(Away-VRL)、接槓瞬間位置距離垂直參考線之水平位置(CB-VRL)、水平移動範圍(HTR)、拋物線範圍(PR)、槓鈴被推離身體後的最大水平速度(MaxVh)與槓鈴在最大垂直高度時的水平速度(MHVh)達顯著差異(p<.05)，另外有兩個垂直運動學參數：槓鈴最大垂直高度(MH)與垂直移動範圍(VTR)達顯著差異(p<.05)，且兩組別都存在不同的槓鈴軌跡運動型態。結論與建議：RBM指數是為一個合理有效的評估選手抓舉技術表現之參考指標，透過此指數分組後，發現優組別與中組別選手存在著不同的槓鈴軌跡型態與技術動作特徵，且優組別在接槓瞬間較中組別來的遠離垂直參考線右側。

Purpose: The purpose of this study was to investigate the barbell trajectory of the snatch champion lifters at the 2010 World University Weightlifting Championship. These lifters were divided into 2 groups by RBM. Methods: A digital camera was used to record the barbell trajectories of the lifters during the snatch. The barbell kinematic parameters were obtained by a motion analysis software. The differences of these parameters between the better group and the middle group were compared. Results: The comparison of 7 barbell horizontal kinematic parameters showed that the XCK， Away-VRL， CB-VRL， HTR PR， Max Vv and MHVh were significantly different between the 2 groups (p < .05). In addition， the 2 barbell vertical kinematic parameters including MH and VTR were significantly different between the 2 groups (p < .05). Conclusions: The RBM is a useful index to evaluate the ability of snatch lifters. It is able to differentiate the differences in barbell trajectory and technical style between the better group and the middle group. The barbells were located farther to the right of the vertical reference line at the instance of catching in the better group compared to the middle group.